platform: dce: Add suspend resume hooks

Add suspend resume hooks function and handling of sc7 events.

Bug 3583331
Bug 3826630

Signed-off-by: Mahesh Kumar <mahkumar@nvidia.com>
Change-Id: I920b02ad46a76330febe666fe17e8d328f744b1d
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvidia/+/2834856
Reviewed-by: Arun Swain <arswain@nvidia.com>
GVS: Gerrit_Virtual_Submit <buildbot_gerritrpt@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvidia/+/2824218
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: svc-mobile-cert <svc-mobile-cert@nvidia.com>
Reviewed-by: svc_kernel_abi <svc_kernel_abi@nvidia.com>

drivers/platform/tegra/dce/Makefile

@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
-# Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 #
 # Display Controller Engine code.
 #
@@ -34,6 +34,7 @@ tegra-dce-$(CONFIG_TEGRA_DCE) += \
 	dce-ipc-signal.o \
 	dce-client-ipc.o \
 	dce-module.o \
+	dce-pm.o \
 	dce-util-common.o
 
 ifeq ($(CONFIG_DEBUG_FS),y)

drivers/platform/tegra/dce/dce-admin.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2022, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2019-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -471,6 +471,79 @@ out:
 	return ret;
 }
 
+/**
+ * dce_admin_send_prepare_sc7 - Sends DCE_ADMIN_CMD_PREPARE_SC7 cmd.
+ *
+ * @d - Pointer to tegra_dce struct.
+ * @msg - Pointer to dce_ipc_msg struct.
+ *
+ * Return - 0 if successful
+ */
+int dce_admin_send_prepare_sc7(struct tegra_dce *d,
+			    struct dce_ipc_message *msg)
+{
+	int ret = -1;
+	struct dce_admin_ipc_cmd *req_msg;
+	struct dce_admin_ipc_resp *resp_msg;
+
+	if (!msg || !msg->tx.data || !msg->rx.data)
+		goto out;
+
+	req_msg = (struct dce_admin_ipc_cmd *)(msg->tx.data);
+	resp_msg = (struct dce_admin_ipc_resp *) (msg->rx.data);
+
+	req_msg->cmd = (uint32_t)DCE_ADMIN_CMD_PREPARE_SC7;
+
+	ret = dce_admin_send_msg(d, msg);
+	if (ret) {
+		dce_err(d, "Error sending prepare sc7 command [%d]", ret);
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
+/**
+ * dce_admin_send_enter_sc7 - Sends DCE_ADMIN_CMD_ENTER_SC7 cmd.
+ *
+ * @d - Pointer to tegra_dce struct.
+ * @msg - Pointer to dce_ipc_msg struct.
+ *
+ * Return - 0 if successful
+ */
+int dce_admin_send_enter_sc7(struct tegra_dce *d,
+			     struct dce_ipc_message *msg)
+{
+	int ret = -1;
+	struct dce_admin_ipc_cmd *req_msg;
+	struct dce_admin_ipc_resp *resp_msg;
+
+	if (!msg || !msg->tx.data || !msg->rx.data)
+		goto out;
+
+	req_msg = (struct dce_admin_ipc_cmd *)(msg->tx.data);
+	resp_msg = (struct dce_admin_ipc_resp *) (msg->rx.data);
+
+	req_msg->cmd = (uint32_t)DCE_ADMIN_CMD_ENTER_SC7;
+
+	ret = dce_ipc_send_message(d, DCE_IPC_CHANNEL_TYPE_ADMIN, msg->tx.data, msg->tx.size);
+	if (ret) {
+		dce_err(d, "Error sending enter sc7 command [%d]", ret);
+		goto out;
+	}
+
+	/* Wait for SC7 Enter done */
+	ret = dce_wait_interruptible(d, DCE_WAIT_SC7_ENTER);
+	if (ret) {
+		dce_err(d, "SC7 Enter wait was interrupted with err:%d", ret);
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
 static int dce_admin_setup_clients_ipc(struct tegra_dce *d,
 		struct dce_ipc_message *msg)
 {

drivers/platform/tegra/dce/dce-bootstrap.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2022, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2019-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -151,7 +151,7 @@ int dce_handle_boot_complete_received_event(struct tegra_dce *d, void *params)
  *
  * Return : 0 if successful else error code
  */
-static int
+int
 dce_start_boot_flow(struct tegra_dce *d)
 {
 	int ret = 0;
@@ -241,8 +241,12 @@ void dce_handle_irq_status(struct tegra_dce *d, u32 status)
 					 NULL);
 	}
 
-	if (status & DCE_IRQ_SC7_ENTERED)
+	if (status & DCE_IRQ_SC7_ENTERED) {
 		dce_info(d, "DCE can be safely powered-off now");
+		(void)dce_fsm_post_event(d,
+					 EVENT_ID_DCE_SC7_ENTERED_RECEIVED,
+					 NULL);
+	}
 
 	if (status & DCE_IRQ_LOG_READY) {
 		dce_info(d, "DCE trace log buffers available");

drivers/platform/tegra/dce/dce-fsm.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -53,11 +53,15 @@ static struct dce_event_process_struct event_process_table[] = {
 	},
 	{
 		.event			= EVENT_ID_DCE_SC7_ENTER_REQUESTED,
-		.fsm_event_handle	= dce_handle_event_stub,
+		.fsm_event_handle	= dce_pm_handle_sc7_enter_requested_event,
 	},
 	{
 		.event			= EVENT_ID_DCE_SC7_ENTERED_RECEIVED,
-		.fsm_event_handle	= dce_handle_event_stub,
+		.fsm_event_handle	= dce_pm_handle_sc7_enter_received_event,
+	},
+	{
+		.event			= EVENT_ID_DCE_SC7_EXIT_RECEIVED,
+		.fsm_event_handle	= dce_pm_handle_sc7_exit_received_event,
 	},
 	{
 		.event			= EVENT_ID_DCE_LOG_REQUESTED,
@@ -178,6 +182,11 @@ dce_fsm_set_state(struct tegra_dce *d,
 		fsm->requested_ipcs &= ~DCE_BIT(DCE_WAIT_SC7_ENTER);
 		break;
 
+	case EVENT_ID_DCE_SC7_EXIT_RECEIVED:
+		fsm->c_state = STATE_DCE_FSM_IDLE;
+		fsm->requested_ipcs = 0;
+		break;
+
 	case EVENT_ID_DCE_LOG_REQUESTED:
 		fsm->c_state = STATE_DCE_LOG_READY_WFI;
 		fsm->requested_ipcs |= DCE_BIT(DCE_WAIT_LOG);
@@ -355,11 +364,16 @@ dce_fsm_validate_event(struct tegra_dce *d,
 		}
 		break;
 	case STATE_DCE_SC7_ENTERED:
-		//
+		switch (event) {
-		// STATE_DCE_SC7_ENTERED is short lived state for now
+		case EVENT_ID_DCE_SC7_EXIT_RECEIVED:
-		// FSM can expect only EVENT_ID_DCE_FSM_START event here
+			ret = 0;
-		//
+			break;
-		dce_err(d, "Event received while in STATE_DCE_SC7_ENTERED state");
+		default:
+			dce_err(d, "Invalid event received [%d] state:[%d]\n",
+				event, curr_state);
+			ret = -EINVAL;
+			break;
+		}
 		break;
 	default:
 		dce_err(d, "Invalid state:[%d] event received [%d]\n", curr_state,

drivers/platform/tegra/dce/dce-module.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2023, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2019-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -59,6 +59,19 @@ static inline struct tegra_dce *dce_get_pdata_dce(struct platform_device *pdev)
 	return (&((struct dce_device *)dev_get_drvdata(&pdev->dev))->d);
 }
 
+/**
+ * dce_get_tegra_dce_from_dev - inline function to get the tegra_dce pointer
+ *						from devicve struct.
+ *
+ * @pdev : Pointer to the device data structure.
+ *
+ * Return :  Pointer pointing to tegra_dce data structure.
+ */
+static inline struct tegra_dce *dce_get_tegra_dce_from_dev(struct device *dev)
+{
+	return (&((struct dce_device *)dev_get_drvdata(dev))->d);
+}
+
 /**
  * dce_init_dev_data - Function to initialize the dce device data structure.
  *
@@ -273,11 +286,35 @@ static int tegra_dce_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int dce_pm_suspend(struct device *dev)
+{
+	struct tegra_dce *d = dce_get_tegra_dce_from_dev(dev);
+
+	return dce_pm_enter_sc7(d);
+}
+
+static int dce_pm_resume(struct device *dev)
+{
+	struct tegra_dce *d = dce_get_tegra_dce_from_dev(dev);
+
+	return dce_pm_exit_sc7(d);
+}
+
+const struct dev_pm_ops dce_pm_ops = {
+	.suspend = dce_pm_suspend,
+	.resume  = dce_pm_resume,
+};
+#endif
+
 static struct platform_driver tegra_dce_driver = {
 	.driver = {
 		.name   = "tegra-dce",
 		.of_match_table =
 			of_match_ptr(tegra_dce_of_match),
+#ifdef CONFIG_PM
+		.pm	= &dce_pm_ops,
+#endif
 	},
 	.probe = tegra_dce_probe,
 	.remove = tegra_dce_remove,

drivers/platform/tegra/dce/dce-pm.c

@@ -0,0 +1,175 @@
+/*
+ * Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <dce.h>
+
+#define CCPLEX_HSP_IE 1U /* TODO : Have an api to read from platform data */
+
+static void dce_pm_save_state(struct tegra_dce *d)
+{
+	d->sc7_state.hsp_ie = dce_hsp_ie_read(d, CCPLEX_HSP_IE);
+}
+
+static void dce_pm_restore_state(struct tegra_dce *d)
+{
+	uint32_t val = d->sc7_state.hsp_ie;
+
+	dce_hsp_ie_write(d, val, CCPLEX_HSP_IE);
+}
+
+/**
+ * dce_resume_work_fn : execute resume and bootstrap flow
+ *
+ * @d : Pointer to tegra_dce struct.
+ *
+ * Return : void
+ */
+void dce_resume_work_fn(struct tegra_dce *d)
+{
+	int ret = 0;
+
+	if (d == NULL) {
+		dce_err(d, "tegra_dce struct is NULL");
+		return;
+	}
+
+	ret = dce_fsm_post_event(d, EVENT_ID_DCE_BOOT_COMPLETE_REQUESTED, NULL);
+	if (ret) {
+		dce_err(d, "Error while posting DCE_BOOT_COMPLETE_REQUESTED event");
+		return;
+	}
+
+	ret = dce_start_boot_flow(d);
+	if (ret) {
+		dce_err(d, "DCE bootstrapping failed\n");
+		return;
+	}
+}
+
+/**
+ * dce_handle_sc7_enter_requested_event - callback handler function for event
+ *					 EVENT_ID_DCE_SC7_ENTER_REQUESTED
+ *
+ * @d : Pointer to tegra_dce struct.
+ * @params : callback params
+ *
+ * Return : 0 if successful else error code
+ */
+int dce_pm_handle_sc7_enter_requested_event(struct tegra_dce *d, void *params)
+{
+	int ret = 0;
+	struct dce_ipc_message *msg = NULL;
+
+	msg = dce_admin_allocate_message(d);
+	if (!msg) {
+		dce_err(d, "IPC msg allocation failed");
+		goto out;
+	}
+
+	ret = dce_admin_send_enter_sc7(d, msg);
+	if (ret) {
+		dce_err(d, "Enter SC7 failed [%d]", ret);
+		goto out;
+	}
+
+out:
+	dce_admin_free_message(d, msg);
+	return ret;
+}
+
+/**
+ * dce_handle_sc7_enter_received_event - callback handler function for event
+ *					 EVENT_ID_DCE_SC7_ENTER_RECEIVED
+ *
+ * @d : Pointer to tegra_dce struct.
+ * @params : callback params
+ *
+ * Return : 0 if successful else error code
+ */
+int dce_pm_handle_sc7_enter_received_event(struct tegra_dce *d, void *params)
+{
+	dce_wakeup_interruptible(d, DCE_WAIT_SC7_ENTER);
+	return 0;
+}
+
+/**
+ * dce_handle_sc7_exit_received_event - callback handler function for event
+ *					 EVENT_ID_DCE_SC7_EXIT_RECEIVED
+ *
+ * @d : Pointer to tegra_dce struct.
+ * @params : callback params
+ *
+ * Return : 0 if successful else error code
+ */
+int dce_pm_handle_sc7_exit_received_event(struct tegra_dce *d, void *params)
+{
+	dce_schedule_work(&d->dce_resume_work);
+	return 0;
+}
+
+int dce_pm_enter_sc7(struct tegra_dce *d)
+{
+	int ret = 0;
+	struct dce_ipc_message *msg = NULL;
+
+	/*
+	 * If Bootstrap is not yet done. Nothing to do during SC7 Enter
+	 * Return success immediately.
+	 */
+	if (!dce_is_bootstrap_done(d)) {
+		dce_debug(d, "Bootstrap not done, Succeed SC7 enter\n");
+		goto out;
+	}
+
+	msg = dce_admin_allocate_message(d);
+	if (!msg) {
+		dce_err(d, "IPC msg allocation failed");
+		ret = -1;
+		goto out;
+	}
+
+	dce_pm_save_state(d);
+
+	ret = dce_admin_send_prepare_sc7(d, msg);
+	if (ret) {
+		dce_err(d, "Prepare SC7 failed [%d]", ret);
+		ret = -1;
+		goto out;
+	}
+
+	ret = dce_fsm_post_event(d, EVENT_ID_DCE_SC7_ENTER_REQUESTED, NULL);
+	if (ret) {
+		dce_err(d, "Error while posting SC7_ENTER event [%d]", ret);
+		ret = -1;
+		goto out;
+	}
+
+out:
+	dce_admin_free_message(d, msg);
+	return ret;
+}
+
+int dce_pm_exit_sc7(struct tegra_dce *d)
+{
+	int ret = 0;
+
+	dce_pm_restore_state(d);
+
+	ret = dce_fsm_post_event(d, EVENT_ID_DCE_SC7_EXIT_RECEIVED, NULL);
+	if (ret) {
+		dce_err(d, "Error while posting SC7_EXIT event [%d]", ret);
+		goto out;
+	}
+out:
+	return ret;
+}

drivers/platform/tegra/dce/dce-worker.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2022, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
+ * Copyright (c) 2019-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -85,7 +85,13 @@ int dce_work_cond_sw_resource_init(struct tegra_dce *d)
 
 	ret = dce_init_work(d, &d->dce_bootstrap_work, dce_bootstrap_work_fn);
 	if (ret) {
-		dce_err(d, "fsm_start work init failed");
+		dce_err(d, "Bootstrap work init failed");
+		goto exit;
+	}
+
+	ret = dce_init_work(d, &d->dce_resume_work, dce_resume_work_fn);
+	if (ret) {
+		dce_err(d, "resume work init failed");
 		goto exit;
 	}
 

drivers/platform/tegra/dce/include/dce-fsm.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -32,6 +32,7 @@ enum dce_fsm_event_id_type {
 	EVENT_ID_DCE_ADMIN_IPC_MSG_RECEIVED,
 	EVENT_ID_DCE_SC7_ENTER_REQUESTED,
 	EVENT_ID_DCE_SC7_ENTERED_RECEIVED,
+	EVENT_ID_DCE_SC7_EXIT_RECEIVED,
 	EVENT_ID_DCE_LOG_REQUESTED,
 	EVENT_ID_DCE_LOG_READY_RECEIVED,
 	EVENT_ID_DCE_ABORT_RECEIVED,

drivers/platform/tegra/dce/include/dce-pm.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef DCE_PM_H
+#define DCE_PM_H
+
+#include <dce.h>
+
+struct dce_sc7_state {
+	uint32_t hsp_ie;
+};
+
+int dce_pm_enter_sc7(struct tegra_dce *d);
+int dce_pm_exit_sc7(struct tegra_dce *d);
+void dce_resume_work_fn(struct tegra_dce *d);
+int dce_pm_handle_sc7_enter_requested_event(struct tegra_dce *d, void *params);
+int dce_pm_handle_sc7_enter_received_event(struct tegra_dce *d, void *params);
+int dce_pm_handle_sc7_exit_received_event(struct tegra_dce *d, void *params);
+
+#endif

drivers/platform/tegra/dce/include/dce.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2022, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2019-2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -25,6 +25,7 @@
 #include <dce-thread.h>
 #include <dce-worker.h>
 #include <dce-fsm.h>
+#include <dce-pm.h>
 #include <dce-mailbox.h>
 #include <dce-client-ipc-internal.h>
 #include <dce-workqueue.h>
@@ -148,6 +149,14 @@ struct tegra_dce {
 	 * dce_bootstrap_work : dce work to be executed to start FSM flow
 	 */
 	struct dce_work_struct dce_bootstrap_work;
+	/**
+	 * dce_resume_work : dce work to executed dce resume flow
+	 */
+	struct dce_work_struct dce_resume_work;
+	/**
+	 * dce_sc7_state : structure to save/restore state during sc7 enter/exit
+	 */
+	struct dce_sc7_state sc7_state;
 	/**
 	 * dce_wait_info - Data structure to manage wait for different event types
 	 */
@@ -377,6 +386,7 @@ const char *dce_get_fw_name(struct tegra_dce *d);
 int dce_driver_init(struct tegra_dce *d);
 void dce_driver_deinit(struct tegra_dce *d);
 
+int dce_start_boot_flow(struct tegra_dce *d);
 void dce_bootstrap_work_fn(struct tegra_dce *d);
 int dce_start_bootstrap_flow(struct tegra_dce *d);
 int dce_boot_interface_init(struct tegra_dce *d);
@@ -402,6 +412,10 @@ int dce_admin_send_cmd_echo(struct tegra_dce *d,
 			    struct dce_ipc_message *msg);
 int dce_admin_send_cmd_ext_test(struct tegra_dce *d,
 				struct dce_ipc_message *msg);
+int dce_admin_send_prepare_sc7(struct tegra_dce *d,
+			       struct dce_ipc_message *msg);
+int dce_admin_send_enter_sc7(struct tegra_dce *d,
+			     struct dce_ipc_message *msg);
 int dce_admin_handle_ipc_requested_event(struct tegra_dce *d, void *params);
 int dce_admin_handle_ipc_received_event(struct tegra_dce *d, void *params);
 int dce_admin_ipc_wait(struct tegra_dce *d, u32 w_type);